Cambridge & Pearson Edexcel Past Paper Questions
Browse 35,704 questions from Cambridge O-Level & A-Level and Pearson Edexcel IGCSE & IAL exams. Click any question to practice.
A mixture of two Period 3 oxides are added to water. A solution forms with a pH of just below 7. What could be the constituents of the mixture?
Which statement about the compounds of the Group 2 metals is correct?
A 0.005 mol sample of anhydrous calcium carbonate is completely thermally decomposed to give 100 cm³ of gas. In a separate experiment carried out u...
Redox reactions are common in the chemistry of Group 17 elements. Which statement is correct?
Silver chloride and silver iodide form equilibria when added to water. AgCl(s) ⇌ Ag⁺(aq) + Cl⁻(aq) K = K₁ AgI(s) ⇌ Ag⁺(aq) + I⁻(aq) K = K₂ Each equ...
X is the ion of a metal which burns with a red flame. Y is an ion that reacts with concentrated H2SO4 to produce H2S. What could be the formula of ...
Oxides of nitrogen are present in the environment due to natural and man-made sources. Which row is correct?
Magnesium hydroxide dissolves in aqueous ammonium chloride, but not in aqueous sodium chloride. Which statement explains this observation?
The formula of hydrocortisone acetate is shown. [Figure of hydrocortisone acetate structure] Which row is correct?
Bromomethane, CH3Br, decomposes in the stratosphere forming methyl free radicals and bromine free radicals. Which row correctly describes this deco...
Structural and stereoisomerism should be taken into account when answering this question. Y is a gaseous hydrocarbon which decolourises aqueous bro...
Butanoic acid can be made from 1-bromopropane in two stages. stage 1 CH3CH2CH2Br → CH3CH2CH2CN stage 2 CH3CH2CH2CN → CH3CH2CH2CO2H Which types of r...
Compound P is heated under reflux with an excess of acidified potassium dichromate(VI) to form compound Q. Compound Q has a lower boiling point tha...
Structural and stereoisomerism should be taken into account when answering this question. An organic compound, X, is dehydrated by heating with con...
Which compound produces a precipitate with 2,4-dinitrophenylhydrazine reagent and also with alkaline aqueous iodine?
Organic compound Z has an alcohol group and a carboxylic acid group. Compound Z reacts with magnesium carbonate to make a salt with a relative form...
The infra-red spectrum of Y is shown. [Figure showing an infra-red spectrum with transmittance % vs wavenumber /cm⁻¹] What could Y be?
The Boltzmann distribution diagram shows a fixed amount of a gas at two different temperatures, T₁ and T₂. [Figure of Boltzmann distribution diagra...
Four solutions, each of concentration 0.1 mol dm⁻³, were tested with a pH meter. The results are shown. solution | formula of acid or base | pH ---...
Which reactions are redox reactions? 1 Mg + 2HCl → MgCl2 + H2 2 2K2CrO4 + 2H⁺ → K2Cr2O7 + 2K⁺ + H2O 3 CuCO3 + 2HCl → CuCl2 + H2O + CO2
When the liquid N2F4 is heated, it decomposes into a single product, X. Which statements are correct? 1 N-F bonds are broken during this decomposit...
The following statements compare some properties of the oxides and chlorides of sodium and silicon. Which statements are correct? 1 The melting poi...
Which statements about ammonium chloride are correct? 1 It reacts with hot aqueous sodium hydroxide to produce an alkaline gas. 2 In solution, it r...
What is the same for a pair of optical isomers? 1 their empirical formula 2 their functional groups 3 their structural formula
Which of the molecular formulae represent at least one compound that can undergo addition polymerisation? 1 C4H8 2 C2H3Cl 3 C3H6O
Which of the reactions give products containing a chiral centre? 1 CH2(OH)COCO2H + an excess of HCN 2 CH2(OH)COCO2H + an excess of NaBH4 3 CH2(OH)C...
Ethyl butanoate is heated with a dilute aqueous solution of sodium hydroxide. Which substances are products of this reaction? 1 sodium butanoate 2 ...
Sulfides are compounds that contain sulfur but not oxygen.
The reaction scheme shows some reactions of calcium. [Figure 2.0]
Phosphorus is a reactive Period 3 element.
Compound B is a liquid with a fruity smell. [Figure 4.0] The reaction scheme shows how B can be made from ethanol, C2H5OH. [Figure 4.1]
Hydrogen iodide, HI, is a colourless gas at room temperature.
(a) Table 1 gives physical data for some of the Period 3 elements. [Figure 2.1]
Compound T is an isomer of C₆H₁₂. [Figure 3.1 shows the structure of T, 2,3-dimethylbut-2-ene]
The reaction scheme shows some reactions of calcium. [Figure: Reaction scheme showing Ca(s) to Ca(NO₃)₂(aq) via HNO₃ (reaction 1), then to Ca(OH)₂(...
Compound B is a liquid with a fruity smell. [Structure of B: an ethyl ester of bromoethanoic acid, CH₃CHBrCOOCH₂CH₃] The reaction scheme shows how ...
In this experiment you will titrate a solution of the hydroxide of a Group 1 element, Z, with sulfuric acid. The equation for the reaction is shown...
Group 1 metal carbonates have the formula M₂CO₃. The identity of the metal ion, M⁺, may be determined by a gravimetric method. The metal carbonate ...
The identity of a Group 1 metal carbonate may also be found by a titration method. M⁺ in this question may or may not be the same cation as that in...
When dilute sulfuric acid is electrolysed, water is split into hydrogen and oxygen. 2H2O(l) → 2H2(g) + O2(g) A current of xA is passed through the ...
Solution Y is hydrochloric acid, HCl(aq). Solution Z is aqueous 4-chlorobutanoic acid, Cl(CH2)3CO2H(aq). The pKa of Cl(CH2)3CO2H(aq) is 4.52. The p...
Some data relating to calcium and oxygen are listed. Select relevant data from this list for your answers to parts (c), (d) and (e). [Table of proc...
Separate samples of 0.02 mol of calcium carbonate and 0.02 mol of barium carbonate are heated until completely decomposed to the metal oxide and ca...
[MnCl₄]²⁻ is a complex ion.
An excess of sodium iodide is added to a solution of copper(II) sulfate. Iodine and a white precipitate of copper(I) iodide are formed.
The structure of phenylethanoic acid is shown. [Figure X.X showing the structure of phenylethanoic acid]
Phenylamine, C₆H₅NH₂, and ethylamine, C₂H₅NH₂, can be distinguished by adding aqueous bromine.
Compound T is made by a three-stage synthesis. [Figure X.X showing the synthesis pathway for Compound T from phenylethanoic acid]
Valine (Val) and lysine (Lys) are amino acids. The structures of these amino acids can be found in the Data Booklet. The isoelectric point of an am...
Radium is a Group 2 element. The predicted lattice energy, ∆H°latt, of radium sulfide, RaS, is –2612kJ mol⁻¹. Some data relating to radium and sul...